Synthesis of Silver Nanostructures on Different Supports: From Nanoparticle Decoration to a Complete Shell Growth

Abstract

In this work, we investigate a complete strategy to obtain supported silver nanostructures (AgNSs) which can be used for different applications such as catalysis, optoelectronics, and biomedical devices. Given the poor wetting of silver on many support materials, the anchorage of silver nanoparticles to the substrate (decoration) is achieved by employing an oxide precipitation‐decomposition method. This protocol is optimized to obtain rapid and homogeneous decoration of silver nanoparticles on different substrates such as silica, titania, and hydroxyapatite with a negligible production of free‐standing silver nanoparticles. Going a step further, we have also studied the growth of silver nanoparticles attached to silica spheres (SiO2NPs) using a seed‐mediated growth strategy. The interplay of different processes which are radial growth, corrosion, coalescence, and electrochemical sintering determines the morphological features of the grown nanoparticles. Therefore, the substrate coverage and nanoparticle morphology can be qualitatively modified controlling the composition of the growth bath. The observed growth is consistent with a radial growth mechanism which, in most experimental conditions, leads to anisotropic AgNSs onto silica surface. In addition, if the corrosion effects are minimized, coalescence process of neighboring particles can give rise to high surface coverage.